Bounce flash power guestimation?

AJQS

AJQS

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Are there any rules of thumb to help with this? I've got a few key power setting memorised for direct flash use, but is there anything I can use to help get the power right when boucning off ceilings etc?
 
It used to be said, one stop for the extra distance (from flash to ceiling to subject) and one more for the surface diffusion, but I think that's not enough.

It obviously depends a lot on the situation, but in an average room if you shoot direct flash and get correct exposure, you'll need about three stops more power (or ISO or f/number) to match that with bouncing. Something of that order - it's very power hungry.
 
As Hoppy says, depends on a lot of things. Start off with a couple of stops on flash compensation, and see where it takes you. Once you get the exposure you want, lock that in, and continue with the rest of the shoot. Unless the ceiling shape changes in the room, the variation should be minimal.
 
HoppyUK said:
you'll need about three stops more power (or ISO or f/number) to match that with bouncing. Something of that order - it's very power hungry.
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That could be do-able, cheers :thumbs:


hairboy said:
As Hoppy says, depends on a lot of things. Start off with a couple of stops on flash compensation, and see where it takes you. Once you get the exposure you want, lock that in, and continue with the rest of the shoot.
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Not possible with a mnaual flash and a roll of film unfortunately! :naughty:

I will try and get round there with a digital thing and see if I can try out the exposure pre event and work from there, otherwise ballpark guesswork and the lattitude of Fuji 800Z will have to do the rest!
 
Alan Clogwyn said:
Not possible with a mnaual flash and a roll of film unfortunately! :naughty:

I will try and get round there with a digital thing and see if I can try out the exposure pre event and work from there, otherwise ballpark guesswork and the lattitude of Fuji 800Z will have to do the rest!
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Get a light meter that can wait for a flash.. Sekonic 308 is a small, simple and affordable favorite. You'll get your exposures right without guessing :)
 
Alan Clogwyn said:
That could be do-able, cheers :thumbs:




Not possible with a mnaual flash and a roll of film unfortunately! :naughty:

I will try and get round there with a digital thing and see if I can try out the exposure pre event and work from there, otherwise ballpark guesswork and the lattitude of Fuji 800Z will have to do the rest!
Click to expand...

Well, if you are using manual flash and film, then you need to work it out the proper way, using the guide number, work out the light - bounce surface - subject, then dial that number in. it's actually more predictable than TTL in a lot of ways.

If you have a handheld lightmeter, it makes your job even easier. No guessing required.
 
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